under-employment (n.) under-employed (adj.) under-achiever (n.) under (prep., adv.) under prep. 在……下面；在……表面下；在……的后面；（职务、级别）低于；少于；比……年轻；由……控制；根据；在……过程中；受……影响；承受着；以（某一名字）；在……项下；在（某个系统）下；在……期间；在……生存条件下；栽有；在……掌权期间；在……手下工作 adv. 在下面；在水下；少于；较年轻；在昏迷中； adj. 较低的；下面的undeniable (adj.) undemonstrative (adj.) undemanding (adj.) undelivered (adj.) undefined (adj.) undefinable (adj.) undefiled (adj.) undefended (adj.) undefeated (adj.) undecisive (adj.) undecipherable (adj.) undecided (adj.) undecennial (adj.) undeceived (adj.) undeceive (v.)